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Sept. 3, 1929. r R. SHQRTETAL Re. 17,425

AIR CLEANING DEVICE ori inal Filed-Nov. 17. 1919 I mwg &mw+w- ReissudSept. 3, 1929.

UNITED STATES Re. 17,425 PATENT OFFICE.

CHARLES R. SHORT, OF DAYTON, OHIO, AND ARTHUR L. CASH, OF MARINE CITY,MICHIGAN, ASSIGNORS TO A G SPARK PLUG COMPANY OF FLINT, MfCHIG-AN, A

CORPORATION OF MICHIGAN.

AIR- CLEANING DEVICE.

Original No. 1,461,630, dated Our invention relates to air cleaningdevices designed for use in connection with internal combustion enginesto prevent the entrance of dust or dirt into the carburetor, and fromthence into the working cylinder of the engine; and particularly to aircleaning devices of the centrifugal type and-in which the flow of airthrough the same is unobstructed as by the use of screens, or by thepresence of a body of water through which the air flows, as hasheretofore commonly been the case in air cleaning devices. Such aircleaning devices are used extensively with tractors designed for use inhauling agricultural machinery, in which service the dust present in theair causes abrasion of the pistons and cylinders, and a rapid wearingout of the engine, if it is permitted to pass through the carburetor andinto the same.

The object of our invention is to provide an improved air cleaningdevice. of the centrifugal type which will be simple in construction andeffective for the purpose of separating dirt from the air which passesthrough the same and. to the carburetor; the said device having featuresof construction and operation whereby the dirt is more effectivelyseparated from the air, and a cleanersupply of air secured for thecarbureter of the engine, than has heretofore commonly been the case.

Our invention is illustrated in its preferred form in the drawingaccompanying and forming a part of this specification; although it willbe appreciated that the drawing is for illustrative purposes only, andfor the purpose of enabling our invention to be clearly understood; andthat our invention includes all such variations and modifications of theparticular embodiment thereof illustrated as come within the scope ofthe concluding claims.

Referring now to the drawing wherein the preferred embodiment of ourinvention is illustrated Fig. 1 is a view showing an internal combustionengine in outline, and in side elevation, the same being equipped withour im proved air cleaning device. I

Fig. 2 is a view showing the engine and air cleaning device inelevation, and seen from a position to the left of Fig. 1.

Fig. 3 is a view showing the lower end of July 10, 1923, Serial No.338,723,. filed November 17, 1.919. Application for reissue filed July6, 1925.

Serial No. 41,868.

the air cleaning device in section and upon a larger scale than in Fig.1.

Fig. 11s a view showing a section upon a transverse plane indicated bythe line 4-4,. Fig. 3.

an internal combustion engine of any kind or type to which combustiblemixture is supplied through an inlet manifold 71eading from a carbureter8 of any preferred form. The engine as shown is-provided with a fan 9,the purpose of which is to cause air to flow past the engine to therebycool or assist in cooling same, as is usual in internal combustionengine practice, the fan being'dri en from the crankshaft 10 through asuitable belt 11.

Our improved centrifugal air cleaning device comprises a casing 12 whichis preferably. of approximately circular form in cross-section,a'nd'which casing is shown as arranged in an inclined position with itsinletend 13 located adjacent the fan 9, so that the fan will tend toforce air into the casing under slight pressure. is preferablyprovided'with a flaring or funnel shaped portion 14: surrounding thesame, to thereby collect air from the stream of air into the casing ofthe cleaner; the action of the funnel being in the nature of a scoop toincrease the supply of air to the casing of the cleaner, and to causethe air within the casing to be at a pressure slightly greater than thepressure of the surrounding atmosphere. We wish here to distinctlystate, however, that our improved air cleaner is capable of use inpositions in which its inlet end is not located adjacent a cooling fan,or even with engines in which such a fan is not used; the flow of airthrough the casing under such circumstances being due entirely to thesuction action of the engine,. whereas when the casing is so arrangedthat the fan creates a flow of air thereinto an increased flow of airdue both to the action of the fan and to the suction of the engine issecured.

The inlet end of the casing established by the fan and direct the sameThe particles of dust, grit and other foreign matter which are carriedthereinto with the stream of air entering the casing 12 are separatedfrom the air by centrifugal action, such action being due to rotarymotion imparted to the stream of air as it flows through the casing andas the result of which motion the particles of foreign matter are thrownto the outer portion of the body of air in accordance with well knownphysical phenomena.

The rotary motion above referred to is imparted to the stream of airflowing through the casing by a spirally arranged member 15 illustratedas in the form of a partition, although said member need not extendentirely across the interior of the casing, and which member preferablyextends throughout a part only of the length of the casing 12 in theform, of our invention illustrated and thus provides a chamber 16between the inner end, of the spirally arranged partition. and the outerand discharge or outlet end of the casing. This whirling motion of theair may be increased by the use of spiral or inclined bafiles 17 locatedwithin the flaring funnel shaped inlet portion 14 of the casing, al

though in many cases the spiral partition 15 will be found sufficient toimpart sufficient rotary motion to the air to secure the separation offoreign matter therefrom by centrifugal action. It will be noted thatmembers 15 and 17 are longitudinally inclined in the direction of theaxis of the casing; that is, instead of being curved in a radialdirection only, they are longitudinally inclined as well so that the airis set whirling and, at the same time, directed along the 'conduit tothecarburetor.

The casing 12 is provided with an opening or slot 18 extendinglongitudinally of the same a-ndpreferably throughout the entire lengththereof, said slot being shown as provided by causing the side edges ofthe sheet of metal from which the casing 12 is formed to overlap oneanother, as best shown in Fig. 5, and by spacing said side edges apartfrom one another. The rotary motion imparted to the stream'of airflowing through the casing causes the particles of dust and otherforeign matter tomove to the outside of the mass of air' by centrifugalforce," as

said particles are heavier than the air, and, as the body of aircontinues to rotatewithin the casing, said particles pass out throughthe slot 18 one edge of which preferably pro-- jects slightly inward toact as a skimming means; such action being materially enhanced by thepresence of the chamber 16 of. considerable volume within the casing andwithin which chamber the body of air is in rotary motion, and alongwhich chamber the opening or slot 18 extends throughout the entirelength thereof in the embodiment of ourinvention illustrated. Theseparation of the dust particles from the stream of air flowing throughthe casing is also materially assisted and a cleaner supply of airsecured because of the fact that the fan 9 is continu ously forcing airinto the casing, thus tendair outlet conduit through which the airpasses from the interior of the casing to the carbureter 8 for use inthe formation of the combustible mixture. This air conduit preferablyextends through the head 18 and for some little distance into theinterior of the casing, and is provided within the casing with one ormore openings 20 through which the airflows from the casing into theoutlet conduit. The portion of the outlet conduit which is within thecasing is preferably made conical in form, in order that its presencemay interfere to the least possible extent with the rotary motion of thebody of-air within the chamber 16, and the fact that the inner end ofsaid air outlet conduit is spaced apart from.the wall of the casingprovides a scheme whereby the air which flows to the carburetor is takenfrom the central portion of the mass of air within the casing, at whichlocality the air is the most free from ,foreign matter; as such foreignmatter tends to pass to the outer limits of the rotating body of air andout through the slot 18, because of the centrifugal force resulting fromthe rotary motion imparted to the air. It will be noted that the cap 18'and the adjacentportion ofthe casing 12 provide an annular dust trapsurrounding the clean air outlet 19. This trap is normally-occupied by awhirling body of air containing fine dust particles having insufficientmomentum to effect their discharge through slot 18.

Attention is also called to the fact that 18- and the clean air outletopenings 20 are" each of much less cross section than the cas ing 12.The action of the fan in supplying air to the casing 12 tends to offsetthe influence of air friction and, if desired, may be made to insuresubstantially the same normal presdust outlet or slot A tional area thansaid casing at the other end thereof, and-which casing 1s provided witha slot extending longitudinally and throughout the entire lengththereof; and a spirally ar-' ranged member located within said casingand extending throughout a part only of the 7 length thereof, and whichmember is adapted to impart rotary motion to .air flowing through saidcasing; said spirally arranged member being located adjacent the inletend of said casing whei'ebv aninternal chamber is provided adjacent theoutlet end of said caslng.

2. In a centrifugal air cleaner, an elongated easing having an air inletopening at one end thereof, and which casing is provided with a slotextending longitudinally thereof; a spirally formed partition locatedwithin'said casing and extending throughout apart only of the lengththereof, whereby a chamber is 3 provided within said casing and beyondthe end of said partition and which partition is adapted to impartrotary motion to air flow ing through said casing; and an air outletconduit extending into thechamber aforesaid 40 at the end of said casingopposite said air inlet and having an opening through which air mayflow, the area of said air outlet conduit being less than the area ofsaid casing; 3. In a centrifugal air cleaner, an elongated casing havingan air inlet opening at one end thereof, and which casing is providedwith a slot extending longitudinally' thereof; a spirally arrangedpartition located within said casing and adapted to impart rotarymotion-to air flowing therethrough; an internal chamber located adjacentthe outlet end of said casing and an air outlet conduitextending intosaid chamber and spaced apart from theperiph'eral wall thereof andhaving an 7 opening through which air may flow from said chamber, theportion of said outlet conduit Within said chamber being conical in formand spaced apart from the wall thereof;

4:. In a centrifugal air cleaner; an elon- 0 gated casing approximatelycircular in cross- I section and having an air inlet opening at one endthereof, and which casing is provided with a slot extendinglongitudinally 'and throughout the entire length thereof; a spi- '85rally arranged member located within said casing and extendingthroughout a part only of the length thereof, and" which member isadapted to impart rotary motion to'air flow ing through said casing;and; an air outlet conduit extending into the endof said caslng oppositesaid air inlet and having an opening in its side walls through which airmay flow from said casing, said conduit being conical in form withinsaidcasing and the wall thereof being spaced apart from'the wall of saidcasing.

5. In combination in an internal combustion engine having a fan forcausing air to flow past the same, a centrifugal air cleaner comprisingan elongated casing having an air inlet opening located adjacentsaidfan,

and an outlet opening of less cross-sectional area than said casingthrough which air may flow to the carbureter of the engine, and whichcasing is provided with a permanently open slot extending longitudinallyand throughout approximatel the entire len h,

thereof; and through w ich, air may ow directly tothe surroundingatmosphere and a spirally arranged member located within said casing andextending throughout a part only of the length. thereof, and whichmember is adapted to impart rotary motion to the'air flowing throughsaid casing.

6. In combination with a carbureter, air supply means therefor includinga conduit in which airflows in a whirling stream to there by separateimpurities therefrom, said means including an air conduit having alaterally perforated substantially conical end-projecting into saidconduit substantially in line with the axis thereof.

7.In combination with a carbureter, air

supply means therefor including a casing through which the air advancestoward the carbureter in a whirling stream, said casing being arrangedwith its axis disposed at," a considerable angle to the vertical, saidcasing also having a narrow slot along its underside in permanently opencommunication with the surrounding atmosphere and through whichimpurities are discharged by centrifugal action.

8. In combination with the carbureter of an internal combustion engine,a centrifugal air cleaner leading thereto and comprising an elongatedeasing having an air inlet opening at one end thereof and which casingis provided with an outlet slot, a spirally formed parti tionlocatedwithin said casing and extending throughout a part only of the lengththereof whereby a chamber is provided Within said 'casing and beyond theend .of said partition,

and which partition is adapted to impart rotary motion to air flowingthrough said casing, and an air outlet conduit extending into thechamber aforesaid at the end of said casing opposite said air inlet,thearea of said air outlet conduit being less than the area of said casing.

rally formed partition located within said casing and extendingthroughout a part only of the length thereot whereby a chamber is Iprovided within said casing and beyond the end of said partition. andwhich partition is adapted to impart rotary motion to air flowingthrough said casing, and an axial air outlet Conduit connnunicating withthe casing at one end thereof. the area of said air outlet conduit beingless than the area of said casing.

10. In combination'with a source of suction, acentrifugal air cleanerleading thereto comprising a casing of substantially circularcross-section provided atone end with an air inlet arranged to impart awhirling motion to the air entering the casing, said casing beingprovided with a clean air outlet of reduced cross-section compared withthe cross-section of the casing, said outlet extending along the axis ofthe casing and being connected with the source of suctionfor supplyingit with cleaned airfrom the region within the casing adjacent to theaxis, and said casing being of thin material and provided at the otherend and radially outward of the clean air outlet with a dust dischargeslot arranged for the tangential discharge of dust, said slot being opento the atmosphere and being of relativel" small size so that, when thecleaner is used with a source of suction only, the small volume of airentering the cleaner therethrough is ineffective to prevent simultaneousdischarge of dust particles through the slot into the surroundingatmosphere.

11. In combination with a source of suction, a centrifugal air cleanerleading thereto comprising a casing of substantially circularcross-section provided at one end with an air inlet arranged to impart awhirling motion to the air entering the using, said casing beingprovided with a clean air outlet of reduced cross-section compared withthe crossse'ction of the casing, said outlet extending along the axis ofthe casing and being connected with the source of suction for supplyingit with cleaned air from the region within the casing adjacent to theaxis. and said casing being of thin material and provided at the otherend and radiallv outward of the clean air outlet with a dust dischargeslot in its side wall having its edges slightly offset in a radialdirection to provide a restricted passage tor the tangential dischargeof dust, said slot being open to the atmosphere and its size being suchthat, when the c eaner is used with a'source of suction only, the smallvolume of air entering the cleaner therethrough is ineffective toprevent simultaneous discharge of dust DQUtUlLSllll'OllfIll the slotinto the surrounding atmosphere.

tures.

CHARLES SHORT. -ARTI-IUR L. oasn'.

